This study aims at comparing caesarean section rates and neonatal outcomes of two
perinatal models of care provided in private hospitals in Brazil. Birth in
Brazil data, a national hospital-based cohort conducted in the years 2011/2012
was used. We analysed 1,664 postpartum women and their offspring attended at 13
hospitals located in the South-east region of Brazil, divided into a "typical” –
standard care model and "atypical" – Baby-Friendly hospital with collaborative
practices between nurse-midwives and obstetricians on duty to attend deliveries
in an alternative labour ward. The Robson’s classification system was used to
compare caesarean sections, which was lower in the atypical hospital (47.8% vs.
90.8%, p < 0.001). Full term birth, early skin-to-skin contact, breastfeeding
in the first hour, rooming-in care, and discharge in exclusive breastfeeding
were more frequent in the atypical hospital. Neonatal adverse outcome did not
differ significantly between hospitals. The atypical hospital’s intervention
should be further evaluated since it might reduce caesarean section prevalence
and increase good practices in neonatal care.

Caesarean sections are almost universal among women who give birth financed by
private funds in Brazil; the proportion of this procedure in this group is
nearly 90% 1. The association
between caesarean sections and private health care is well documented and occurs
in developed and developing countries 2,3,4,5,6. However, none of these countries has as high a
caesarean section prevalence as that reported for the private sector in Brazil.
The World Health Organization (WHO) sets an upper limit of 15% as appropriate
for caesarean section prevalence on medical grounds 7,8. Based on this, there are no clinical reasons that
can justify a caesarean section prevalence of 90%. This prevalence suggests that
critical, non-clinical factors play a role in the process of clinical
decision-making surrounding the type of birth. Probably there are local
contextual determinants, especially those related to the health system 9, in the causal chain of this
problem.

The health system in Brazil mixes public and private financing 10. The access to the public
sector is universal 10. Part
of the public care is carried out in certain private hospitals, known as mixed
hospitals, which can have both beds contracted by the government and those paid
through private funds 10. In
addition, there are some private hospitals which assist only private patients,
in this case there are two options: patients can pay providers directly (out of
pocket payment), which is less common, or pay for private health insurance 10. This paper focuses on women
who had maternity care paid through private funds in private hospitals,
excluding mixed hospitals.

According to official data 11
from December 2012, 24.7% of the Brazilian population had at least one private
health insurance plan, with this coverage varying by region throughout the
country. The Southeast is the richest region of Brazil and the states that make
up this region have the highest coverage of private health insurance, ranging
from 25.9% to 43.6% 11. There
are around 20 million women at fertile age (10 to 45 years old) in this region,
which represents 31% of the overall number of women at fertile age in Brazil
(Departamento de Informática do SUS. Informações de saúde (Tabnet): estatísticas
vitais. Mortalidade e nascidos vivos.
http://www2.datasus.gov.br/DATASUS/index.php?area=0206, accessed on
25/Jun/2013).

Studies 12,13,14,15 conducted in cities located
in the Southeast region of Brazil of women who use private health insurance have
found a prevalence of caesarean section ranging from 80% to 90%.

The standard perinatal model of care for people who use private health insurance
in Brazil has the following characteristics: antenatal care and delivery are
provided by the same doctor, who is paid by private health insurers in a
fee-for-service reimbursement system and who is responsible for covering
antenatal care appointments during weekday office hours and for attending labour
and birth 12. There are very
few births attended independent nurse-midwives in this sector.

Since 2004, the National Regulatory Agency for Private Health Insurance and Plans
(ANS) has been studying strategies to reduce caesarean section prevalence in the
private sector in Brazil. In line with this, technicians from the ANS have
identified one private hospital whose managers reported an innovative perinatal
model of care, which was the reason why it was chosen for comparison and that
will be referred to as an “atypical hospital” in this paper. The main features
of this model were: the antenatal care team is different from the delivery care
team; there is collaborative labour and birth assistance between nurse-midwives,
and physicians, who are paid by monthly salary regardless of the number of
deliveries. The atypical hospital is located in a non-capital city in the
Southeast region of Brazil and is a referral to maternity services in this
region for women insured by the health plan that owns the hospital.

Evidence suggests that there is an association between higher proportions of
caesarean sections and non-clinical factors, such as: the fee-for-service as
payment type 16 and deliveries
in obstetric unit instead of midwifery-led units 17 or instead of other kinds of alternative hospitals
or freestanding settings of birth 18. In addition, previous studies 12,13,14,15 have found that private care is strongly
associated with the high prevalence of caesarean sections in Brazil.

According to the WHO report 9,
aspects related to health systems, such as human resources and financing
profiles, have the largest impact on caesarean section prevalence and should
receive more attention in research on this topic. From this perspective, the
hypothesis of this paper is that the atypical hospital’s perinatal model of care
might have a significant effect on caesarean section prevalence and neonatal
outcomes. Considering this hypothesis, this study aims at comparing the
caesarean section prevalence and neonatal outcomes of women who gave birth at
the atypical hospital with those of women who gave birth in private hospitals
that adopt the standard perinatal model of care (typical hospitals), taking into
account women’s characteristics.

Methods

This study was a sub-project of a national hospital-based cohort study of
postnatal women and their offspring called Birth in Brazil19. Clinical criteria for
participants’ eligibility were: postnatal women who gave birth to a live newborn
of any weight or gestational age or to a stillbirth with birth weight ≥ 500g
and/or gestational age ≥ 22 weeks of pregnancy.

For this analysis, the group exposed to the innovative perinatal model of care
was formed by women who gave birth in the atypical hospital. The unexposed group
was formed of women who gave birth in private hospitals located in non-capital
cities in the Southeast Region of Brazil sampled in the Birth in
Brazil study.

Setting and participants

A probabilistic sample in three stages was designed for the Birth in
Brazil study. Firstly, hospitals with 500 or more births in
2007 were selected randomly with the probability proportional to the number
of live births per hospital in 2007 in each of the 30 strata defined for the
study. Then, the number of days that would be necessary (a minimum of 7
days) to reach a fixed number of 90 postpartum women in each hospital was
defined. Finally, the women and their offspring were selected randomly, with
equal probability, in each one of the 266 hospitals selected in the first
stage, totalling 23,940 postnatal women and their offspring 20.

There were 86 private hospitals eligible for the Birth in
Brazil study in non-capital cities of the Southeast of Brazil.
In this stratum, 13 private hospitals, at least one in each of the four
states that form the region, were randomly selected. The atypical hospital
was among these 13 private hospitals. In order to estimate the atypical
hospital caesarean section prevalence and neonatal outcomes, a random sample
of this hospital was calculated based on a late preterm births (from 34 to
36 weeks of gestational age) prevalence of 8%, with 5% of significance to
detect differences of at least 5% and with testing power of 80%. A finite
population correction was used based on the number of births in the atypical
hospital in 2007 (2.507 births). The minimum sample size calculated for the
atypical hospital was 503 postnatal women and their offspring. Following the
90 interviews performed in the atypical hospital during the Birth in
Brazil field work, 512 further interviews were completed in
this hospital, compounding the exposed group. The unexposed group was made
up of women who gave birth in one of the other 12 private hospitals,
totalling 1,080 women; the atypical hospital was excluded from this group.
The sample weights were based on the inverse of the inclusion probabilities
in the sample.

Data collection

Fieldwork was carried out between February 2011 and October 2012 and the
measurement instruments were the same as those used during the Birth
in Brazil study (see the instruments in the additional files
and more information about the fieldwork in the study protocol) 19. A woman’s face-to-face
electronic questionnaire, collected in the hospital between 6 to 24 hours
after birth, was the first one used; information on patients’ and newborns’
medical records was assessed using a second electronic questionnaire,
completed after death or discharge from hospital, or at maximum on the
42nd hospitalization day for the woman and the
28th hospitalization day for the newborn. A folder with a
summary of the antenatal appointments and obstetric ultrasonography was
photographed, when available. This was used to access relevant data, such as
gestational age in the early pregnancy. A specific electronic form was used
for the data extraction from these photos. In addition, the managers of
hospitals were interviewed by the supervisor to assess hospital facilities,
using a face-to-face paper-format questionnaire.

Statistical analysis

The occurrence of caesarean sections was the primary outcome; secondary
outcomes comprised: (1) gestational age in weeks, which was determined using
an algorithm 21 that
reduced the chance of miscalculating the gestational age, acknowledging the
Brazilian context; (2) early skin-to-skin contact (holding the baby or
breastfeeding just after birth vs. visual contact or no
contact at all); (3) breastfeeding in the first hour after birth; (4)
rooming-in care during all hospitalization; (5) discharge in exclusive
breastfeeding and (6) adverse neonatal outcome, a composite dichotomy
variable including neonatal mortality – death of a live-born infant in the
first 28 days of life – or neonatal near miss 22, which comprises the presence of any of
the following: birth weight < 1,500g, Apgar score at the 5th minute of
life < 7, mechanical ventilation, gestational age < 32 weeks and
congenital malformations.

Independent variables were: maternal age in years (< 20; 20 to 34; 35 or
more); skin colour (white; black; brown/mixed; Asian; indigenous); years of
schooling (7 or less; 8 to 10; 11 to 14; 15 or more); economic status
(measured using the ABEP index, which is a score based on family level of
consumption and level of education of the head of the family) (Associação
Brasileira de Empresas de Pesquisa. Critério de classificação econômica
Brasil 2010. http://www.abep.org, accessed on 30/Jun/2013); marital status
(living with partner or not); women classification based on obstetrically
relevant concepts (Robson’s 10-group classification); and high risk
pregnancy (yes or no).

The Robson’s 10-group classification system was developed in 2001 23 based on the following
obstetric concepts at the time of delivery: the category of pregnancy
(single or multiple and cephalic or non-cephalic); the previous obstetric
record of the woman (nulliparous or multiparous, with or without uterine
scar); the course of labour and delivery (spontaneous, induced or caesarean
sections before labour) and the gestational age at the time of delivery. The
10 groups formed from these concepts (Table 1 and 2) are
mutually exclusive but totally inclusive and clinically relevant. Robson’s
10-group classification is the best method for institutional comparison of
the mode of delivery 24.
It was used to assess differences between the atypical and typical hospitals
regarding: the relative size of the groups (total number of women in each
group divided by total number of women who give birth); the overall
proportion of caesarean sections and the proportion of caesarean sections in
each group (number of caesarean sections in each group divided by number of
women who give birth in each group); contribution of each group to the
overall proportion of caesarean sections (number of caesarean sections in
each group divided by total number of women who gave birth) and proportion
of vaginal births (number of vaginal births in each group divided by total
number of women who gave birth).

Variables related to social and demographic maternal characteristics, early
skin-to-skin contact and all others related to breastfeeding were extracted
from the woman’s face-to-face electronic questionnaire; occurrence of
caesarean sections, adverse neonatal outcome, high risk pregnancy and
Robson’s 10-group classification were taken from medical records; data
related to hospital organization and the perinatal model of care, such as
availability of neonatal intensive care unit, type of providers, schedules
of labour and delivery care team, accreditation as a Baby-Friendly Hospital
and availability of non-pharmacological features for pain relief during
labour, were extracted from the face-to-face questionnaire with the manager
of the hospital.

To analyse whether proportional distributions of the independent variables
differed significantly (p-value at least 0.05) between the atypical hospital
and typical hospitals, the Wald test for homogeneity was used. Independence
between outcomes and type of hospital was explored using a second-order
Rao-Scott adjusted chi-square test (p-value at least 0.05 to be considered
significant). Statistical analyses were performed using the package complex
survey samples in the R 2.15.2 software (The R Foundation for Statistical
Computing, Vienna, Austria; http://www.r-project.org).

The study was funded by the Brazilian National Research Council (CNPq) of the
Brazilian Ministry of Science and Technology and by the Oswaldo Cruz
Foundation (Fiocruz) of the Brazilian Ministry of Health. The National
School of Public Health (Ensp/Fiocruz) Research Ethics Committee approved
this study (opinion no. 92/10). Eligible women were invited to participate
in the study after reading a detailed consent form. Consent was digitally
obtained, with the woman receiving a printed version.

Results

In total, 1,788 women were invited to participate; 629 in the atypical hospital
and 1,159 in the typical hospitals; 6% of those eligible women were not
interviewed (108 women) – 4.6% in the atypical hospital (29 women) and 6.8% in
the typical hospitals (79 women) because of early discharge or because they did
not want to participate. In addition, 16 women in the atypical hospital (2.5%)
were excluded because the medical record questionnaires were not completed.
These women did not differ to those included in analysis in relation to the
variables “age” and “mode of delivery”. This analysis included 584 women who
gave birth in the atypical hospital and 1,080 women who gave birth in typical
hospitals.

The atypical and typical hospitals were akin in relation to geographic location
and type of hospital financing – all hospitals assisted only private patients
and are based in non-capital cities of the South-east region of Brazil.
According to the manager of these hospitals, the atypical hospital had a
neonatal intensive care unit (neonatal ICU) and was referral for high-risk
pregnancies; among typical hospitals seven in twelve (58.3%) had neonatal ICU
and four in twelve (33.3%) were referral to high-risk pregnancies. The atypical
hospital was the only one that held the Baby-Friendly Hospital accreditation,
offered non-pharmacological features for pain relief during labour (bath;
birthing ball; rocking/birth chair) and had nurse-midwives attending vaginal
births – 75.9% of overall vaginal birth was attended by nurse-midwives in the
atypical hospital (data not shown in table). Other features of the atypical
hospital perinatal model of care were adopted by very few typical hospitals: in
two out of twelve (16.7%) typical hospitals there were periodical meetings to
discuss caesarean sections rate and its indications and in one out of twelve
(8.3%) typical hospitals there was a bath in the labour ward.

Women attended in the atypical and typical hospitals were similar (Table 1); differences in age, skin
colour, years of schooling, income status, marital status and high risk
pregnancy between these two types of hospitals were not statistically
significant. Women differed significantly (p = 0.045) in relation to Robson’s
10-group classification; group 2 (nulliparous, single cephalic, > 37 weeks,
induced or caesarean sections before labour) and group 5 (previous caesarean
sections, single cephalic, > 37 weeks) comprised the highest proportion of
women in both type of hospitals. There were more nulliparous (groups 1 and 2)
and more multiparous with previous caesarean sections (group 5) in typical
hospitals than in the atypical one.

The overall caesarean section prevalence was 1.9 times higher (p < 0.001) in
typical hospitals than in the atypical one, the proportion of caesarean sections
was also higher in typical hospitals compared to the atypical hospitals in most
of the groups of the Robson’s classification (Table 2). The contribution of each group to the overall
proportion of caesarean sections, taking into account the relative size of the
groups, varied according to the type of hospital – group 5, which comprised
women with previous caesarean sections, contributed more to the overall
prevalence of caesarean sections in the atypical hospital (15% of the overall
caesarean sections was in this group), while in typical hospitals group 2, which
included nulliparous, induced or caesarean sections before labour, comprised the
majority of caesarean sections (37.1%). The groups that contributed more to the
overall proportion of vaginal birth in the atypical hospital were groups 4 (12%)
and 2 (11.8%), which included multiparous and nulliparous induced labour; in
typical hospitals, group 3 (3.9%) which included multiparous with spontaneous
labour, contributed more to the overall proportion of vaginal birth.

Caesarean sections before labour (Figure
1) were 2.3 times higher among women who gave birth in typical
hospitals than those in the atypical one (73% vs. 31%, p <
0.001). In typical hospitals, the prevalence of caesarean sections among women
who were classified as low risk pregnancy was nearly the same as those who were
classified as high risk pregnancy (88.6%, vs. 93.4%, p =
0.129). In the atypical hospital, the prevalence of caesarean sections among
women who were classified as high risk pregnancy was more than three times
higher than the prevalence of caesarean sections among low risk pregnancies
(76.1%, vs. 20.7%, p < 0.001).

The atypical hospital presented better neonatal outcomes (Table 3). Interventions that facilitate initiation of
breastfeeding like early skin-to-skin contact between mother and baby,
breastfeeding in the first hour after birth and rooming-in care during all
hospitalization were more frequent in the atypical hospital than in the typical
ones. Although the adverse neonatal outcome rate was higher in the atypical
hospital (32 per 1,000 live births in the atypical hospital and 25 per 1,000
live births in typical hospitals), this difference was not statistically
significant (p = 0.250).

Distribution of gestational age among babies born by caesarean sections was
different according to the type of hospital (Table 4). Most of the babies who were born by caesarean section in
the atypical hospital were full term (born between 39 and 41 weeks of
gestational age); while in typical hospitals the majority of babies born by
caesarean sections were early term (born within 37 or 38 weeks of gestational
age). The prevalence of early terms born by caesarean section was 1.5 times
higher in typical hospitals than in the atypical hospital (51.2%,
vs. 33.8%, p < 0.001). For those babies born by vaginal
birth, differences in gestational age by type of hospital were not statistically
significant (p = 0.103).

Table 4 Distribution of gestational age by type of birth and type of
private hospital. Southeast Region of Brazil, 2011-2012.

Gestational age
(weeks)

Caesarean section

p-value *

Vaginal birth

p-value *

Total

p-value *

Atypical (n = 282)

Typical (n = 971)

Atypical (n = 302)

Typical (n = 109)

Atypical (n = 584)

Typical (n = 1,080)

%

%

%

%

%

%

≤ 33

4.5

2.4

0.001

0.7

3.2

0.103

2.5

2.5

0.001

34-36

7.8

7.6

7.3

11.1

7.5

7.9

37-38

33.8

51.2

37.7

32.3

35.8

49.5

39-41

53.6

38.5

53.8

53.4

53.7

39.8

≥ 42

0.4

0.3

0.6

0.0

0.5

0.3

Total

100.0

100.0

100.0

100.0

100.0

100.0

* Second-order Rao-Scott adjusted chi-square test.

Discussion

Typical hospitals are similar among them and differ from the atypical hospital
regarding characteristics of maternity care management. Features such as
Baby-Friendly Hospital accreditation, availability of non-pharmacological
features for pain relief during labour and nurse-midwives as primarily
responsible for attending vaginal births were observed only in the atypical
hospital, suggesting that the perinatal model of care in the atypical hospital
is innovative when compared with the standard model of care in private hospitals
in the Southeast region of Brazil.

The case-mix of the population included in this study had similar demographic and
obstetric characteristics in both types of hospitals and might not explain the
differences in caesarean section prevalence and neonatal outcomes between the
atypical and typical hospitals. It is therefore most likely improbable that
other women’s characteristics, not included in this study, would be able to
explain the differences observed. These results strongly suggest that
differences in the perinatal model of care explain the considerable variation in
caesarean section prevalence and neonatal outcomes among the atypical and
typical hospitals.

The overall caesarean section prevalence, the proportion of caesarean sections
before labour and the proportions of caesarean sections in most groups of the
Robson’s 10-group classification were remarkably lower among women who gave
birth in the atypical hospital than those who gave birth in typical hospitals.
The difference in the overall caesarean section prevalence between the two types
of hospitals was even higher for women classified as low risk pregnancy. The
reduced overall prevalence of caesarean sections in the atypical hospital could
be due to access restrictions for this type of birth, however the caesarean
section prevalence of 76% among women classified as high risk pregnancy in the
atypical hospital suggest that there was no caesarean section access
restrictions for women who needed this type of birth.

The overall caesarean section prevalence in both types of hospitals was much
higher than the maximum of 15% recommended by the WHO to prevent or treat
life-threatening perinatal complications 7,8. However, the overall caesarean section prevalence
in the atypical hospital was similar to the median caesarean section prevalence
(51%) in private hospitals in Latin America 2 and lower than those reported for low risk women in
private hospitals in Australia 3 (27.1% compared to 20.7%), a country in which the
health system 25 shares
similarities with the Brazilian health system 10 – both formed by a public-private mix, offering
public universal health coverage and private insurance as an option.

In both types of hospitals, group 2 (nulliparous, single cephalic, > 37 weeks,
induced or caesarean sections before labour) followed by group 5 (previous
caesarean sections, single cephalic, > 37 weeks) of the Robson’s 10-groups
classification were the largest. This result was different than expected because
groups 1 and 3, which include all women with single cephalic pregnancy, at >
37 weeks gestation, in spontaneous labour and without uterine scar, are the
biggest groups in the majority of obstetric populations 23. In addition, group 2 in typical hospitals
and group 5 in the atypical hospital were the ones that contributed more to the
overall proportion of caesarean sections. These results suggest that strategies
aiming at reducing caesarean sections in private hospitals in Brazil should give
more emphasis and consider specific actions to groups 2 and 5. In the atypical
hospital, groups 2 and 4 had a high contribution to the overall proportion of
vaginal birth, suggesting that the perinatal model of care in this hospital
focused successfully on these groups, perhaps because of labour induction.
However, reducing caesarean section prevalence among women with previous
caesarean sections (group 5) remains a challenge in both the atypical and
typical hospitals.

The majority of caesarean sections performed in the atypical hospital was after
39 weeks of gestational age as recommended by international guidelines 26,27. On the other hand, in the
typical hospitals, the majority of caesarean sections was performed before 39
weeks. The high prevalence of caesarean sections before labour and the high
frequency of early terms born by caesarean sections in typical hospitals suggest
that a great number of elective caesarean sections were performed before 39
weeks of gestational age in typical hospitals. This is a worrying situation
since elective caesarean sections before 39 weeks increases the risk of neonatal
morbidity 28,29 and of negative long term
outcomes, such as lower reading and mathematics results when compared to full
term children 30.

Although the atypical hospital is a referral service for high risk pregnancy and
neonatal requiring neonatal ICU, there was no difference between the atypical
and typical hospitals regarding adverse neonatal outcomes. In addition, good
practices related to neonatal care – early skin to skin contact, breastfeeding
at first hour after birth, rooming-in care, and discharge in exclusive
breastfeeding – were more frequent in the atypical hospital.

Evidence supports the theory that teams on duty 31 made up of nurse-midwives and obstetricians
working collaboratively to attend women in labour 32, with midwives as the primary person
responsible for attending vaginal births 33,34; audit review of caesarean section prevalence and
its indication 36,36; availability of non-pharmacological features to
support normal labour 18 and
the Baby-Friendly Hospital accreditation 37,38 are strategies adopted by the atypical hospital
that might explain its results. However, it is not clear how all these
strategies interacted and what in particular contributed to the reduced
caesarean section prevalence found in the atypical hospital. The perinatal model
of care of this hospital is likely to be a multifaceted complex intervention
39, with components
regarding maternity management and organization and behavioural change in health
professionals and patients. For a better understanding of how this intervention
worked an in depth examination was necessary 40. To perform such a qualitative research was
carried out in the atypical hospital and will be presented in a future
publication.

The strengths of this study include, firstly, its originality because this is the
first study in Brazil with a sample size and statistical power to compare
private hospitals with pronounced variation on caesarean section prevalence and
its effect on neonatal outcomes. Secondly, this study used the same instruments
and quality control measures of a national survey into labour and birth 19 which contributed to the
minimisation of bias and increased the possibility of comparisons with results
on a national level. The weakness of the study comprises the observational
design which limited the possibility of identifying reliable estimates of
effect; also the possibility that the study did not have the power to detect
differences that may exist regarding adverse neonatal outcomes because of the
low rate of this composite variable.

Conclusion

Our results suggest that evidence-based changes in maternity care might markedly
reduce caesarean section prevalence and increase good practices related to
neonatal care, without an increase in adverse neonatal outcomes in private
hospitals in Brazil. The high proportion of early term births and caesarean
sections before labour may be a matter of ethical concern. The Brazilian Medical
Council should develop recommendation in order to reduce elective caesarean
sections, especially those before 39 weeks of gestational age and before labor,
following what has been done in other countries. Further research exploring
features of the innovative perinatal model of care of the atypical hospital
would better explain which key aspects policy makers should focus on in order to
develop interventions to reduce caesarean sections and improve neonatal outcomes
in private sector in Brazil.

Acknowledgments

We thank Camilla Alexsandra Schneck and Antonieta Keiko Kakuda Shimo for
coordinating the fieldwork in the atypical hospital and all those people who
contributed with provision of data to this study. We also thank regional and
state coordinators, supervisors, interviewers and crew of the study and the
mothers who participated and made this study possible.

National Council for Scientific and Technilogical Development (CNPq); Science
and Tecnology Department, Secretariat of Science, Tecnology, and Strategic
Inputs, Brazilian Ministry of Health; National School of Public Health,
Oswaldo Cruz Foundation (INOVA Project); and Foundation for supporting
Research in the State of Rio de Janeiro (Faperj).

J. A. Torres proposed the design and objectives, conducted statistical
analyses, interpretation of results and wrote the first and final versions
of the article. R. M. S. M. Domingues, J. Sandall, Z. Hartz, S. G. N. Gama,
M. M. Theme Filha, A. O. C. Schilithz and M. C. Leal contributed to the
interpretation of results, and read, revised and approved the final version
of the manuscript.

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